There was a time when RMK went from having a individual stamp for their marking stainless blades with S, to integrating the S with their RMK stamp. Here are what I think are two examples. The Micarta 5-4’s stamp appears lighter at the top of the S and right scimitar. So is it a Sep S or the “new” integrated. The knife is an early 70’s knife, about the time the S became inclusive. The stag is a Sep S IMO. The S appears slightly left leaning!